The Division of Cancer Prevention and Control?s Board of Scientific Counselors approved the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial in January 1991. Contracts were awarded in September 1992. Ten Screening Centers (SCs), a Coordinating Center (CC), and a Laboratory (Lab) were competitively selected. Screening began upon OMB approval of study forms in November 1993. The NCI Executive Committee approved Special Studies to investigate research topics using questionnaire and biological data on October 8, 1996. In 2009, the NCI Director approved the continuation of follow-up of PLCO participants beyond the originally planned 13-year follow-up period. As screening had now ended, the next phase of follow-up and associated data collection was thought to be more efficiently collected centrally by a new CDCC. In March 2011, a new contract to the CDCC was awarded (contract number: HHSN261201100008C) to Westat for a period of 5 years to permit centralized follow-up of all PLCO participants who consented to continuation in the study as either active (transfer to CDCC for follow-up activities as previously done at SCs) or passive (remain as PLCO participant through linkages conducted only by the SCs). (To date, a little less than $12,000,000 have been obligated to the contract.) Before the site contracts ended, participants were mailed consent forms informing them of the new centralized follow-up and given three options: 1) consent for active follow-up by transferring all PII and future data collection efforts to the CDCC; 2) consent for passive follow-up by their screening centers including linkages to healthcare databases such as state tumor registries, National Death Index, and Medicaid and Medicare; or 3) withdraw from PLCO. In this effort, nearly 20,000 participants or approximately 15% of the eligible PLCO participants at the time withdrew from the study completely, translating to a significant volume of data loss for this invaluable study. This renewal must be re-awarded to the current CDCC contractor so that we can avoid further data loss; awarding this contract to any other contractor would require another consent process, yielding further data loss which would be detrimental to the PLCO study. Extending follow-up of PLCO participants will add more important data to this rich scientific resource but only with as many eligible PLCO participants as possible. For this task order, implementation of a new questionnaire and initiation of a new specimen collection will increase the value of the PLCO data and specimen resource by allowing new types of analyses for risk factors for cancer